Fuel EXe Trek Fuel EXe Power Application

mctubster

New Member
Jul 18, 2023
10
1
Nelson, NZ
The motor doesn't like a slow cadence, below 70 and it doesn't provide much reward. I look at it as a "bike riders" bike, if you like to ride at 50 rpm it probably isn't for you. I find it hard to believe that most or any of us ride consistently over 100 rpm, pro cyclist - probably, amateur - low probability.
Bosch bike riders always seem to be cruising at low rpm ;) ... I find the Gen4 motors to be crazy powerful on a mountain bike. I have one on a Cargo bike that is 200KG laden and that is when you need all the power you can get!
 

Sonars

New Member
Aug 30, 2023
2
1
04261
Hi all, new to this forum. I recently purchased a Trek Fuel Exe 9.8 XT. I love the bike but... over the week and a half I've had the bike (about 5 pretty rugged rides averaging 20 miles or so) I gradually started experiencing a problem that may be relevant to this thread. The problem is intermittent assist from the motor. The first time it happened I had taken a break in the middle of a ride and when went to restart after 5 minutes or so there was little or no power assist. I shut down and restarted the bike and this seemed to clear the issue, riding another 10 miles or so without an issue. This problem grew more frequent ride over ride, to the point where it cannot be reset. Separately, I had been intrigued by the power meter and had been watching it from time to time. When the bike was working properly, the meter would show my input varying from 0 to 300 W and a somewhat proportional motor assist up to 99 W as i was riding, in low power mode with default settings. When the problem occurs, my power shows 0 all the time, no matter how hard or fast I pedal in any power mode. The motor does put out some assist, especially when I stop pedaling for a moment and then restart. I also bumped it to high power mode while climbing in this condition and I could intermittently feel sudden surges of power, but only for fractions of a second. Also, and this is odd. when the problem is occurring, the low and high power indicators on the display dim slightly, but noticeably, otherwise they are bright a consistent. Odd, but I was able to use this to know that there was a problem no matter what screen I had displayed.

So, the bike is back in the shop being looked at. The mechanic seems to feel I have a "failed" sensor module in the motor. But he needed to do a full check up.. firmware, wiring etc, before doing a warranty replacement of the motor, assuming we go down that path. I did find one reference to this problem in a youtube post that seemed to align with this. Here:
I'll post again when I get the plan from the shop..
 

Sonars

New Member
Aug 30, 2023
2
1
04261
Hi all, new to this forum. I recently purchased a Trek Fuel Exe 9.8 XT. I love the bike but... over the week and a half I've had the bike (about 5 pretty rugged rides averaging 20 miles or so) I gradually started experiencing a problem that may be relevant to this thread. The problem is intermittent assist from the motor. The first time it happened I had taken a break in the middle of a ride and when went to restart after 5 minutes or so there was little or no power assist. I shut down and restarted the bike and this seemed to clear the issue, riding another 10 miles or so without an issue. This problem grew more frequent ride over ride, to the point where it cannot be reset. Separately, I had been intrigued by the power meter and had been watching it from time to time. When the bike was working properly, the meter would show my input varying from 0 to 300 W and a somewhat proportional motor assist up to 99 W as i was riding, in low power mode with default settings. When the problem occurs, my power shows 0 all the time, no matter how hard or fast I pedal in any power mode. The motor does put out some assist, especially when I stop pedaling for a moment and then restart. I also bumped it to high power mode while climbing in this condition and I could intermittently feel sudden surges of power, but only for fractions of a second. Also, and this is odd. when the problem is occurring, the low and high power indicators on the display dim slightly, but noticeably, otherwise they are bright a consistent. Odd, but I was able to use this to know that there was a problem no matter what screen I had displayed.

So, the bike is back in the shop being looked at. The mechanic seems to feel I have a "failed" sensor module in the motor. But he needed to do a full check up.. firmware, wiring etc, before doing a warranty replacement of the motor, assuming we go down that path. I did find one reference to this problem in a youtube post that seemed to align with this. Here:
I'll post again when I get the plan from the shop..
Here's the update... The shop replaced the motor, but it did not solve the problem. They then replaced the display and that seemed to fix the issue. I had 2 perfect rides where the bike worked really well with assist as it should be and the display showing the rider input wattage. On the 3rd ride, I suddenly felt the assist go to very low and inconsistent. When I switched to the power screen it once again showed 0 input power no matter how hard I pedaled. The assist comes on but it is a fraction of what it should be and very erratic. The shop is closed today, so I'll drop it off for a second round of trouble shooting tomorrow. It seems all that is left is the remote, wiring harness and battery.

Does anyone have experience with trek replacing a new bike when its had a repeating problem in the 1st 3 weeks of ownership? I'm thinking of asking for a new bike, rather than waiting and wondering if it'll be fixed on the next round.
 

steveL

Member
Nov 11, 2022
36
41
Southeast BC
I'm having a problem where my power input indicated is lower than the actual input. I am basing this on my HR, perceived effort and previous rides on the same hill. It seems to get " stuck" in the 40 to 60 watt range. In one case it seemed to self correct and went back to a believable 120- 140 watt range( HR was reduced). In the second event I had to turn the bike off twice to get back to a "normal" power output. The first time this happened I noticed it because I felt like I was riding in sand, so it is a noticeable event by the feel and then when I checked power output it verified the feeling.

It also may have become more surgy - not sure about that.

I ride at a reasonable cadence; 75- 100 rpm, average cadence at the end of the ride will normally be in the 80's. I am an experienced rider with a background in road and MTB racing.

I understand that this isn't a calibrated power meter.

I did find one other post that seemed to have a similar event, I believe that a software update fixed that one. My software all got updated last week. Anyone else experience this or have "informed" thoughts.

Thanks,

Steve
 
Last edited:

Mteam

E*POWAH Elite
Aug 3, 2020
1,872
1,807
gone
I'm having a problem where my power input indicated is lower than the actual input. I am basing this on my HR, perceived effort and previous rides on the same hill. It seems to get " stuck" in the 40 to 60 watt range. In one case it seemed to self correct and went back to a believable 120- 140 watt range( HR was reduced). In the second event I had to turn the bike off twice to get back to a "normal" power output. The first time this happened I noticed it because I felt like I was riding in sand, so it is a noticeable event by the feel and then when I checked power output it verified the feeling.

It also may have become more surgy - not sure about that.

I ride at a reasonable cadence; 75- 100 rpm, average cadence at the end of the ride will normally be in the 80's. I am an experienced rider with a background in road and MTB racing.

I understand that this isn't a calibrated power meter.

I did find one other post that seemed to have a similar event, I believe that a software update fixed that one. My software all got updated last week. Anyone else experience this or have "informed" thoughts.

Thanks,

Steve
are you putting pressure on the pedals when you first turn the bike on? I have a hunch (no hard facts to back this up) that the bike calibrates the torque sensor on startup and if you're putting pressure on the pedals when it starts up then it can under-read your power quite significantly.

If you're not doing this, then sounds like a faulty motor.
 

Swingset

Active member
Sep 9, 2022
276
310
Southern Cal
are you putting pressure on the pedals when you first turn the bike on? I have a hunch (no hard facts to back this up) that the bike calibrates the torque sensor on startup and if you're putting pressure on the pedals when it starts up then it can under-read your power quite significantly.

If you're not doing this, then sounds like a faulty motor.
Interesting- on my Shimano Steps motor if you were loading the pedals during boot up it threw a code. On the TQ I have tried all kinds of scenarios and it seems to not care.
 

steveL

Member
Nov 11, 2022
36
41
Southeast BC
are you putting pressure on the pedals when you first turn the bike on? I have a hunch (no hard facts to back this up) that the bike calibrates the torque sensor on startup and if you're putting pressure on the pedals when it starts up then it can under-read your power quite significantly.

If you're not doing this, then sounds like a faulty motor.
I usually turn it on before I get on it, so that is probably not the problem. Which is too bad as it would be an easy fix.
 

DBSwiss

Member
Oct 25, 2022
107
88
United States
Thank you for the link to that thread. The description sounds very much like what I experienced. Also, I remember now that at times I thought I heard a soft growling/grinding motor noise that didn't sound quite right. The Trek shop diagnostics didn't find anything wrong with the motor.
What you describe is what I had prior to April this year when the firmware was updated. Before then, in boost I would get assistance while accelerating but it would cut out when riding at consistent speed, even if going uphill. The software update improved it BUT I tried a different EXe on the trail and it felt a quite a bit more powerful than mine With the same settings (all maxed out in boost).

the grinding noise is unrelated I think. I still have that on mine as well and it is noticeable only when the motor provides little to no power when pedaling. My bike is an early 9.8 XT (delivered early Oct 2022). I just asked the shop for a new motor under warranty given that it still doesn’t feel like I get the full power.
 

DBSwiss

Member
Oct 25, 2022
107
88
United States
Here's the update... The shop replaced the motor, but it did not solve the problem. They then replaced the display and that seemed to fix the issue. I had 2 perfect rides where the bike worked really well with assist as it should be and the display showing the rider input wattage. On the 3rd ride, I suddenly felt the assist go to very low and inconsistent. When I switched to the power screen it once again showed 0 input power no matter how hard I pedaled. The assist comes on but it is a fraction of what it should be and very erratic. The shop is closed today, so I'll drop it off for a second round of trouble shooting tomorrow. It seems all that is left is the remote, wiring harness and battery.

Does anyone have experience with trek replacing a new bike when its had a repeating problem in the 1st 3 weeks of ownership? I'm thinking of asking for a new bike, rather than waiting and wondering if it'll be fixed on the next round.
I read some comments about the Torque sensor measuring rider input on early bikes was not very good and if that fails, I would think it could produce the issue you mentioned. I wonder if replacing the sensor could fix it.
in regards to your last question, Trek has a 30 day return guarantee for any reason and they seem to stretch that period, especially when you are having some issues that started earlier.
 

Dave_B

E*POWAH Elite World Champion
Aug 29, 2020
1,467
1,593
Newquay
I had this power/assist drop happen to me yesterday a few times through the ride.
Does the app tell you what version of software you are running?
What is the latest version available?
 

Mteam

E*POWAH Elite
Aug 3, 2020
1,872
1,807
gone
I had this power/assist drop happen to me yesterday a few times through the ride.
Does the app tell you what version of software you are running?
What is the latest version available?
The latest software versions are listed here


but there is no way to find out what version you are running without plugging the bike into the dealer diagnostics software
 

superk163

Member
May 14, 2019
4
1
central ny state
Here is a follow up on my post back in July . The local Trek dealer replaced the motor and crank arms no questions asked. I have put a few hundred miles on it since then and the only issue is the motor cuts out occasionally. It does not seem to be heat related as it has done it a few times at low power in cooler temps. The motor is real quiet and power is much more predictable and consistent. I Hope she holds out for the long run !
 

DBSwiss

Member
Oct 25, 2022
107
88
United States
The latest software versions are listed here


but there is no way to find out what version you are running without plugging the bike into the dealer diagnostics software
I usually ask the shop to pull a service report for me which lists the software versions and other details.
 

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